package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import com.baomidou.mybatisplus.core.conditions.Wrapper;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.hmdp.dto.Result;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.Follow;
import com.hmdp.entity.User;
import com.hmdp.mapper.FollowMapper;
import com.hmdp.service.IFollowService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.service.IUserService;
import com.hmdp.utils.UserHolder;
import org.apache.tomcat.util.http.parser.Host;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;
import org.springframework.transaction.jta.UserTransactionAdapter;

import java.time.LocalDateTime;
import java.util.*;
import java.util.stream.Collectors;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class FollowServiceImpl extends ServiceImpl<FollowMapper, Follow> implements IFollowService {
    @Autowired
    private IUserService userService;
    @Autowired
    private StringRedisTemplate stringRedisTemplate;

    /**
     * 是否关注
     * @param followUserId
     * @return
     */
    @Override
    public Result isFollow(Long followUserId) {
        UserDTO user = UserHolder.getUser();
        Long userId = user.getId();
        Integer count = query().eq("user_id", userId)
                .eq("follow_user_id", followUserId)
                .count();
       return  Result.ok(count>0);

    }

    /**
     * 取消关注
     * @param followUserId
     * @param isFollow
     * @return
     */
    @Override
    public Result follow(Long followUserId, Boolean isFollow) {
        UserDTO user = UserHolder.getUser();
        Long userId = user.getId();
        if(isFollow){
            Follow follow = new Follow();
            follow.setFollowUserId(followUserId);
            follow.setFollowUserId(userId);
            boolean save = save(follow);
            //key set
            String key  =   "follows"+ userId;
            stringRedisTemplate.opsForSet().add(key ,String.valueOf(followUserId));

        }
        else {
            remove(new QueryWrapper<Follow>()
                    .eq("user_id", userId).eq("follow_user_id", followUserId));
        }
        return Result.ok();
    }
    @Override
    public Result followCommons(Long id) {
        Long userId = UserHolder.getUser().getId();
        String key = "follows:" + userId;
        // 2.求交集
        String key2 = "follows:" + id;
        Set<String> intersect = stringRedisTemplate.opsForSet().intersect(key,key2);
       if(intersect==null || intersect.isEmpty()){
           return Result.ok(Collections.emptyList());
       }
        List<Long> collect = intersect.stream()
                .map(Long::valueOf)
                .collect(Collectors.toList());
        List<UserDTO> userDTOS = userService.listByIds(collect)
                .stream()
                .map(user -> BeanUtil.copyProperties(user, UserDTO.class))
                .collect(Collectors.toList());
        return Result.ok(userDTOS);
    }
}
//extend ServiceImpl <FollowMapper, Follew>